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Old 07-31-2014, 12:47 AM   #31
des_a
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I don't understand it's output exactly...
 
Old 07-31-2014, 12:54 AM   #32
des_a
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I just got the syntax to work, "I think", by changing the rules to the following:

Code:
if_statement:		IF LEFTP expression
			{
			 conprint("a\n");
			}
			  RIGHTP stmt
			{
			 conprint("b\n");
			}
			| if_statement ELSE stmt
			{
			 conprint("c\n");
			}
			;
Now, if that is correct syntax, I can begin generating code for the output...
 
Old 07-31-2014, 09:17 AM   #33
des_a
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I still can't do it without being able to detect whether or not there is an else there or not. Unfortunately, this does NOT work...

Code:
if_statement:		IF LEFTP expression
			{
			 ++ifcounter;
	
			 String if_body_str = "if_body_";
			 if_body_str += ifcounter - 1;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(if_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("ALOAD TBOOLEAN %s\n", $3.to_boolean().get().getString().c_str());
			 conprint("CGOTOL TVOID %u\n", (ifcounter - 1));
			 conprint("GOTOL TVOID %u\n", ifcounter);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			  RIGHTP stmt
			{
			 // Code for if will be inserted here...
			 cout << elsebegin << endl;
			 if (yychar == ELSE)
			 {
			  String else_body_str = "else_body_";
			  else_body_str += ifcounter;
			  String after_if_str = "after_if_";
 			  after_if_str += ifcounter + 1;

			  labelTable.insert();
			  labelTable[labelTable.length() - 1].name(else_body_str);
			  labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			  labelTable.insert();
			  labelTable[labelTable.length() - 1].name(after_if_str);
			  labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			  conprint("GOTOL TVOID %u\n", ifcounter + 1);
			 }
			 else
			 {
			  String after_if_str = "after_if_";
 			  after_if_str += ifcounter;

			  labelTable.insert();
			  labelTable[labelTable.length() - 1].name(after_if_str);
			  labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			  conprint("GOTOL TVOID %u\n", ifcounter);
			 }

			 conprint("\n\nLBL TVOID 0V\n");
			}
			| if_statement ELSE stmt
			{
			 // Code for else will be inserted here if exists...
			 conprint("GOTOL TVOID %u\n", ifcounter + 1);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			;
 
Old 07-31-2014, 09:44 AM   #34
NevemTeve
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By the way, many years ago I did play with bison, too, here is a file I found under the dust: percpars.y
 
Old 07-31-2014, 10:03 PM   #35
des_a
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So here is my code now:

Code:
if_statement:		IF LEFTP expression
			{
			 ++ifcounter;
	
			 String if_body_str = "if_body_";
			 if_body_str += ifcounter - 1;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(if_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("ALOAD TBOOLEAN %s\n", $3.to_boolean().get().getString().c_str());
			 conprint("CGOTOL TVOID %u\n", (ifcounter - 1));
			 conprint("GOTOL TVOID %u\n", ifcounter);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			  RIGHTP stmt
			{
			 // Code for if will be inserted here...
			 ifbegin = outcount;

			 String after_if_str = "after_if_";
 			 after_if_str += ifcounter;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("GOTOL TVOID %u\n", ifcounter);
			 endifbegin = outcount - 1;


			 conprint("\n\nLBL TVOID 0V\n");
			}
			| if_statement ELSE stmt
			{
			 // Code for else will be inserted here if exists...
			 elsebegin = outcount;

			 String else_body_str = "else_body_";
			 else_body_str += ifcounter;
			 String after_if_str = "after_if_";
 			 after_if_str += ifcounter;

			 labelTable.remove();

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(else_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 char temp[33];
			 ltoa((ifcounter + 1), temp, 10);
			 String temp2 = "GOTOL TVOID ";
			 temp2 += temp;
			 temp2 += "\n";
			 out[endifbegin] = temp2;


			 conprint("GOTOL TVOID %u\n", ifcounter + 1);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			;
But it doesn't work with an if-else ladder yet. It works with all the rest, but not an if else ladder. Code is where it's supposed to be, but the label numbers in the goto statements are off. For example, given this file:

Code:
if (3 + 2)
 ;
else if (false)
 ;
It will generate this code:
Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 1


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 1
GOTOL TVOID 2


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 3


LBL TVOID 0V
GOTOL TVOID 3


LBL TVOID 0V

END TVOID 0V
When it should be generating this code:
Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 3


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 2
GOTOL TVOID 3


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 3


LBL TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V

END TVOID 0V
 
Old 07-31-2014, 11:33 PM   #36
NevemTeve
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That's because 'ifcounter' is a global variable, so the nested if changes its value.

Edit: You can use the parser's stack to save/restore values, eg:
Code:
if:     IF                { $$.ifcounter= ++ifcounter;
                            ++ifnest;
                            fprintf (stderr, "line %ld: before if, set ifcounter to %d, nest=%d\n",
                                lineno, ifcounter, ifnest); 
                            fflush (stderr); }
        '(' expr ')' stmt
        opt_else          { $$.obj = ...; 
                            ifcounter= $2.ifcounter; 
                            --ifnest;
                            fprintf (stderr, "line %ld: after if, reset ifcounter to %d, ifnest=%d\n",
                                lineno, ifcounter, ifnest); 
                            fflush (stderr); };

opt_else:                 { $$.obj = NULL; }
        | ELSE stmt       { $$.obj = $2.obj; };
Last edited by NevemTeve; 08-01-2014 at 09:21 AM.
 
Old 08-01-2014, 04:42 PM   #37
des_a
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I got a little further by moving the ifcounter code. Now it compiles to the following:

Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 0


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 3


LBL TVOID 0V
GOTOL TVOID 3


LBL TVOID 0V

END TVOID 0V
Still wrong, but closer in the fact that it is incremented in a lot better spot...
 
Old 08-07-2014, 11:10 PM   #38
des_a
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Trying to use NevemTeve's suggestion, I now have the following code:

Code:
control_statement:	if_statement { ++ifcounter; }
			;

if_statement:		IF LEFTP expression
			{
			 cout << "if p1: " << ifcounter << endl;
			 String if_body_str = "if_body_";
			 if_body_str += ifcounter;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(if_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("ALOAD TBOOLEAN %s\n", $3.to_boolean().get().getString().c_str());
			 conprint("CGOTOL TVOID %u\n", ifcounter);
			 conprint("GOTOL TVOID %u\n", ifcounter + 1);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			  RIGHTP stmt
			{
			 cout << "if p2: " << ifcounter << endl;
			 // Code for if will be inserted here...
			 ifbegin = outcount;

			 String after_if_str = "after_if_";
 			 after_if_str += ifcounter;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("GOTOL TVOID %u\n", ifcounter);
			 endifbegin = outcount - 1;


			 conprint("\n\nLBL TVOID 0V\n");
			}
			opt_else
			;

opt_else:		| ELSE stmt
			{
			 cout << "else: " << ifcounter << endl;
			 // Code for else will be inserted here if exists...
			 elsebegin = outcount;

			 String else_body_str = "else_body_";
			 else_body_str += ifcounter;
			 String after_if_str = "after_if_";
 			 after_if_str += ifcounter;

			 labelTable.remove();

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(else_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 char temp[33];
			 ltoa((ifcounter + 2), temp, 10);
			 String temp2 = "GOTOL TVOID ";
			 temp2 += temp;
			 temp2 += "\n";
			 out[endifbegin] = temp2;


			 conprint("GOTOL TVOID %u\n", ifcounter + 2);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			;
The output of the program looks okay when run with an if or an if-else:
Code:
if p1: 0
if p2: 0
Code:
if p1: 0
if p2: 0
else: 0
...But not an if-else ladder:
Code:
if p1: 0
if p2: 0
if p1: 0
if p2: 0
else: 1
It should be:
Code:
if p1: 0
if p2: 0
if p1: 1
if p2: 1
else: 0
ifcounter is supposed to count the number of if's in the code. Based off of that, I generate the if statement code.
 
Old 08-07-2014, 11:23 PM   #39
des_a
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I got the ifcounter to work, but surprisingly, it still doesn't work. Given:

Code:
if (3 + 2)
 ;
else if (false)
 ;
It generates:
Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 0


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 1
GOTOL TVOID 2


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 2


LBL TVOID 0V
GOTOL TVOID 2


LBL TVOID 0V

END TVOID 0V
The code should be as stated before.

---------- Post added 08-07-14 at 09:24 PM ----------

Maybe an ifnest is needed?
 
Old 08-07-2014, 11:33 PM   #40
des_a
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ifnest now works, and count up by one if there is an if-else statement in an if-else statement...
 
Old 08-08-2014, 01:42 AM   #41
des_a
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Now it gets tricker...

Here is my code:

Code:
control_statement:	if_statement
			;

if_statement:		IF LEFTP expression
			{
			 ++ifcounter;
			 ifgoto = ifcounter < 2 ? ifcounter : ifcounter + 1;
			 cout << "if p1: " << ifcounter << " " << ifnest << " " << " " << elsecounter << ifgoto << endl;

			 String if_body_str = "if_body_";
			 if_body_str += ifgoto - 1;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(if_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("ALOAD TBOOLEAN %s\n", $3.to_boolean().get().getString().c_str());
			 conprint("CGOTOL TVOID %u\n", ifgoto - 1);
			 conprint("GOTOL TVOID %u\n", ifgoto);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			  RIGHTP stmt
			{
			 cout << "if p2: " << ifcounter << " " << ifnest << " " << elsecounter << " " << ifgoto << endl;
			 // Code for if will be inserted here...
			 ifbegin = outcount;

			 String after_if_str = "after_if_";
 			 after_if_str += ifgoto - 1;

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 conprint("GOTOL TVOID %u\n", ifgoto - 1);
			 endifbegin = outcount - 1;


			 conprint("\n\nLBL TVOID 0V\n");
			}
			opt_else
			{
			 --ifcounter;
			 ++ifnest;
			}
			;

opt_else:		| ELSE stmt
			{
			 ++elsecounter;
			 cout << "else: " << ifcounter << " " << ifnest << " " << elsecounter << " " << ifgoto << endl;
			 
			 // Code for else will be inserted here if exists...
			 elsebegin = outcount;

			 String else_body_str = "else_body_";
			 else_body_str += ifcounter;
			 String after_if_str = "after_if_";
 			 after_if_str += ifgoto - 1;

			 labelTable.remove();

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(else_body_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 labelTable.insert();
			 labelTable[labelTable.length() - 1].name(after_if_str);
			 labelTable[labelTable.length() - 1].address(labelTable.length() - 2);

			 char temp[33];
			 ltoa((ifgoto + 1), temp, 10);
			 String temp2 = "GOTOL TVOID ";
			 temp2 += temp;
			 temp2 += "\n";
			 out[endifbegin] = temp2;


			 ifgoto = elsecounter >= 2 ? ifgoto + 1 : ifgoto;
			 conprint("GOTOL TVOID %u\n", ifgoto + 1);

			 conprint("\n\nLBL TVOID 0V\n");
			}
			;
It generates code correctly in this case:

Code:
if (3 + 2)
 ;
else if (false)
 ;
...and in this case:

Code:
if (3 + 2)
 ;
else if (false)
      ;
     else
      ;

...but NOT in this case:

Code:
if (3 + 2)
{
 ;
}
else if (false)
{
 ;
}
else
 ;
In the last case, it generates:

Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 0


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 2
GOTOL TVOID 3


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
GOTOL TVOID 5


LBL TVOID 0V

END TVOID 0V
When the result should be:
Code:
VERSION TVOID 0V


ALOAD TBOOLEAN true
CGOTOL TVOID 0
GOTOL TVOID 1


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
ALOAD TBOOLEAN false
CGOTOL TVOID 2
GOTOL TVOID 3


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
VOID TVOID 0V
GOTOL TVOID 4


LBL TVOID 0V
GOTOL TVOID 5


LBL TVOID 0V

END TVOID 0V
 
Old 08-08-2014, 03:44 AM   #42
NevemTeve
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It would be an improvement if you used a pseudo-Assembly that actually made sense.

Code:
if (10==20+30) {
   x= 1;
}

LD $r1,10
LD $r2,20
LD $r3,30
ADD $r2,$r3
SUB $r1,$r2
BNZ LABEL_1
LD $r1,1
ST $r1,x
LABEL_1:
 
Old 08-08-2014, 06:57 AM   #43
sundialsvcs
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Why do you think that the rest of us are so dammed interested in watching you debug your compiler?

Why don't you crack-open any book (Ajo or some other, simpler one) that just shows you how it's done? And, be done??
 
Old 08-08-2014, 06:19 PM   #44
des_a
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Here's the documentation for the lower level language(s).
Attached Files
File Type: txt instruction_set.txt (15.8 KB, 12 views)
 
Old 08-08-2014, 06:34 PM   #45
des_a
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I have it compiled to the asm of this language. I am creating a whole set of tools for this language. The intent way down the road is to make it easier to create a whole operating system. Although still very difficult, it's easier to create a program in the lowest level than it is to directly write java bytecode or machine language or an .exe or an elf file.

This language can be as portable as Java, but it is easier to write at it's lowest level, and should be nearly or just as fast. It comes with tools to compile it to native code. The assembler, is a step easier than this language. Then there's this high-level language I'm developing, which is a step easier than the assembler. Then eventually, I'll probably write some code on top of this to make that easier, and so on, so that it is really powerful and easy to use.
 
  


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